1. Field of the Invention
This invention relates to electrically conductive adhesive compositions which are especially useful for bonding together surfaces of electronic devices.
2. Description of the Prior Art
Nonconductive adhesive compositions are well known in the art. For example, U.S. Pat. No. 3,890,407 discloses adhesive compositions consisting essentially of a chlorosulfonated polyethylene, or a mixture of a chlorinated polyethylene and a sulfonyl chloride, in certain polymerizable monomers, such as acrylic monomers, which compositions provide high bond strengths on curing, that is, on polymerization of the monomer. Conductive adhesive compositions which are prepared by adding conductive particles to nonconductive adhesive compositions are also known. Such compositions may require large amounts of solvents to dissolve certain of the components. U.S. Pat. No. 3,140,342 discloses an adhesive composition, useful as a gasket material, comprising a matrix binder, such as a polyvinyl chloride plastisol or a curable silicone or urethane, and conductive particles, such as aluminum, nickel, lead, zinc, cadmium, copper or iron particles coated with a noble metal, such as silver or gold.